<template>
  <div>
    <table border="1" width="700" style="border-collapse: collapse">
      <caption>
        购物车
      </caption>
      <thead>
        <tr>
          <th>
            <input type="checkbox" v-model="isAll" /> <span>全选</span>
          </th>
          <th>名称</th>
          <th>价格</th>
          <th>数量</th>
          <th>总价</th>
          <th>操作</th>
        </tr>
      </thead>
      <tbody>
        <tr v-for="(item,index) in goodList " :key="index">
          <td><input type="checkbox" v-model="item.checked"></td>
          <td>{{item.name}}</td>
          <td>{{item.price}}</td>
          <td><button @click="sub(index)">-</button>{{item.num}}<button @click="add(index)">+</button></td>
          <td>{{item.price*item.num}}</td>
          <td><button @click="shanchu(index)">删除</button></td>
        </tr>
      </tbody>
      <tfoot>
        <tr>
          <td>合计:{{zongjia}}</td>
          <td colspan="5">
          </td>
        </tr>
      </tfoot>
    </table>
  </div>
</template>

<script>


export default {
  data() {
    return {
      goodList: [
        {
          name: "诸葛亮",
          price: 1000,
          num: 1,
          checked: false,
        },
        {
          name: "蔡文姬",
          price: 1500,
          num: 1,
          checked: false,
        },
        {
          name: "妲己",
          price: 2000,
          num: 1,
          checked: false,
        },
        {
          name: "鲁班",
          price: 2200,
          num: 1,
          checked: false,
        },
      ],
    };
  },
  methods: {
    sub(index) {
      // console.log(index);
      this.goodList[index].num > 1 ? this.goodList[index].num-- : []
    },
    add(index) {
      this.goodList[index].num++
    },
    shanchu(index) {
      // console.log(index);
      this.goodList.splice(index, 1)
    }
  },
  computed: {
    isAll: {
      set(val) {
        return this.goodList.forEach(item => item.checked = val)
      },
      get() {
        return this.goodList.every(item => item.checked === true)
      }
    },
    zongjia() {
      return this.goodList.reduce((sum, item) => {
        return sum += item.price * item.num
      }, 0)
    },
  }
};
</script>

<style>

</style>